Xephyr suddenly freezes on you, after some random amount of 10 minutes? You might be victim of Nvidia binary crap hijacking your libGL, replacing it with a dubious one. Make sure there is no nividia in the output of ldd...

The input method doesn’t work inside Xephyr? Sometime you find out that .xsession-errors says Preparation of font set "fixed" for XIM failed. The font path could be wrong. Make sure that the path to misc is the first one in...

I have two screens connected to a powerful box. Mostly, I’m using these for coding and it’s running Xinerama with radeon (sssh don’t say anything). Only sometimes however, I would like to share the machine with a second user. There...